Monday, May 5, 2014

Gunk Engine Degreaser v's Red Diesel

Like many people who have their hands in old car parts, I get through quite a lot of engine degreaser. The brand I have found to be the most effective (and the best smelling) is Gunk. I find Gunk so useful I buy it in 2.5 litre cans which are currently selling in Halfords for £10.99. Making it £4.40ish per litre.
A lot like this one.

I heard a rumour though that diesel was also a pretty good degreaser. There is no real need to purchase the ordinary everyday expensive car diesel either, there is always red diesel which I'm sure will work equally as well and is much cheaper, currently about 79p per litre.

With such a potential saving to be had, I wanted to know just how effective red diesel was when it comes to getting rid of that stubborn black grime.

Off I totted to the fuel station with my little 5 litre can cunningly marked 'Red Diesel'. Of course there were the usual warnings at the pump stating that it's very naughty to use red diesel in your car. Of course I will be using it exclusively for cleaning but I still can't shake the slight feeling of guilt when buying it. Once home and back in the shed though, I got to work on some filth.

After decanting some into a jar, the first thing I noticed was that it isn't red, more of a pink colour, but I guess they didn't want to call it pink diesel. Anyway, the pinkness aside, I started to brush a test patch onto the knackered engine block I have. The block is pretty dirty except for one patch where I had already cleaned it with Gunk. Using the red diesel and cleaned another patch next to the already Gunked spot so I could see the results side by side. I have to say that the initial results were very good. See the pic below. Left side is using Gunk, the right side is using red diesel.

Gunk on the left, red diesel on the right.

As I was using the red diesel, the grime seemingly melted away with the same efficacy as Gunk. I have to say that after trying the diesel on a few other things I had lying around, I was pretty convinced that it was as good as Gunk.

Maybe this is the biggest secret within the car restoration community, or maybe it is common knowledge. Either way, I didn't know how good diesel was at cleaning things. Gunk is very good at it's job, but at £4.40 per litre, it is a no brainer that red diesel at 79p per litre will be my degreaser of choice from now on. (Even if it doesn't smell quite as nice!)

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  1. Wow! I'm glad you did that experiment. The findings you got are pretty good. Maybe it's an unwritten and unworded restoration technique? Hahaha! At any rate, I'm glad you uncovered that secret, Wayne! I hope it's okay for me to spread the news. Thanks for sharing that! Kudos and all the best to you! :)

    Abraham Yates @ Apache Oil Company

    1. Hi Abraham.
      I love writing the blog and it's great to get feedback. Please do spread the news... 'like' the facebook page, subscribe to the youtube channel etc... and let others know. The more the merrier.